VTech UP407 ErisBusinessSystem Accessory Cordless Handset, Silver/Black | Requires a Main Console (UP416) or Extension Deskset (UP406) to Operate Cordless mobility - Stay connected even when you're on the move in the office. The cordless handset extends your mobility. 4-line operation - Manage calls from 1- 4 telephone lines simultaneously.Intercom - Instantly communicate with the other desksets and handsets in the system - no delays, just increased productivity. Cordless handset speakerphone - Free- up your hands to do other things while you keep the conversation going. Requires a Main Console (UP416) or Extension Deskset (UP406) to operate. (Each main console and extension deskset can support only 1 cordless handset (UP407)).